Apparatuses for detecting subsurface objects have been used to detect concealed objects including, without limitation, hidden bombs, narcotics, cables, pipes, and corpses. Such apparatuses also have been used to facilitate subsurface detection in various technology areas, such as for motion detection, seeing-through walls, archeology, and geology. Most notably, however, such apparatuses are used to detect land mines. While apparatuses for detecting subsurface objects, including the invention described herein, may be advantageously employed in various applications, the invention is described herein, in terms of an apparatus for the detection of land mines, with no intent of limitation.
Since 1975, land-mines have exploded under more than 1 million people and are currently thought to be killing approximately 800 people a month. In 64 countries around the world, there are an estimated 110 million land-mines still lodged in the ground. They remain active for decades-years after wars have ended. As such, a large worldwide community has devoted extensive resources to ridding the world of both future and currently placed land mines. Mine detecting technology has been invaluable to this endeavor and has been responsible for preventing the loss of many lives.
There are currently at least four types of mine detection machines available: 1) vehicle mounted; 2) handheld; 3) airborne; and 4) mechanical clearing devices such as rollers, plows, or flails. These mine detection machines detect surface and subsurface anti-tank (“AT”) mines and anti-personnel (“AP”) mines. An AT mine is a type of land mine designed to damage or destroy vehicles, whereas an AP mine is used against humans.
Vehicle mounted detection systems employ one of many sensor technologies to help “see” or detect the mines. Two types of vehicle mounted mine detection systems are shown in FIGS. 1 and 2. For the most part, these vehicle mounted mine detection systems are AT mine overpass and thus will typically not detonate an AT mine because the ground pressure is low enough not to trigger the AT mines. However, all of these AT-overpass vehicle mounted mine detection systems can easily detonate an AP mine. Once a mine is detonated—whether AP or AT—the explosion can severely damage sensors and other parts of the vehicle that are carrying the sensors. The repair and replacement of damaged sensors and vehicle parts is very expensive. Moreover, unless the vehicle is remotely controlled, the operator of the vehicle is in danger of being hit by shrapnel emitted from the exploded mine and the ensuing damaged sensor and vehicle.
The other three types of mine detection machinery also have some disadvantages. Specifically, the use of handheld sensors puts the soldier or de-miner directly in harms way as missed mines can detonate when stepped upon. Moreover, enemy fire may be directed toward the soldier engaged in de-mining. Airborne detection systems have a low probability of detection being too far away from the ground to accurately detect the mines, and as such are not very effective. Mechanical clearing devices such as rollers, plows, and flails are not 100% effective and tend to leave the land in a fragile state by destroying structures and vegetation in the path of detection. This destruction is of particular concern in desert land which has very limited vegetation, such vegetation taking years to develop in remote areas of the arid environment. Moreover, if these mechanical clearing devices detonate an AT mine, they are often damaged beyond repair.
As such, there remains a need for an improved apparatus for detecting subsurface objects such as landmines that is safe and accurate and that concurrently minimizes damage to the environment, sensor and apparatus.